Henry c



(No Model.)

H. 0. SERGEANT. VALVE FOR DIRECT ACTION ENGINES.

No. 545,738. Patented Sept. 3,1895.

NITED STATES PATENT Trio HENRY C. SERGEANT, OFv WESTFIELD, NEW JERSEYASSIGNOR TO THE INGERSOLLSERGEANT DRILL COMPANY, OF NEW YORK, N. Y.

VALVE FOR DIRECT-ACTION ENGINES.

SPECIFICATION forming part of Letters Patent No. 545,738, datedSeptember 3, 1895. 2

Application filed October 4,1894. Serial No. 524,871. (No model.) I

To all whom it may concern.-

Be it known that I, HENRY O. SERGEANT, of Westfield, in the county ofUnion and State of New Jersey, have invented a new and usefulImprovement in Valves for Direct- Action Engines, of which the followingis a specification. p

This invention relates to valves, particularly applicable torock-drilling engines,which are moved in the arcs of circles by means ofinclines which are provided upon the pistons of such engines. Such avalve is the subject of Letters Patent No. 212,598, dated February 25,1879.

One object of this improvement is to reduce the wear of such a valve. I

Another object is to retain the valve in its seat in a proper workingline, and a further object is to provide a more direct passage for thesupply of steam or other motive fluid to the ports in the valve-seat.

I will proceed first to describe my invention in detail, and willafterward point out its novelty in claims.

Figure 1 representsa longitudinal sectional view of portions of thecylinder and piston of a rock-drilling machine, said section being takenthrough the center of the valvechest valve, and ports. Fig. 2 representsa transverse section in the line 2 2 of Fig. 1. Fig. 3 represents aninside view of the valve-chest and a back view of the valve therein.

Similar letters and numerals of reference designate corresponding partsin all the figures.

A is the cylinder, having on one side of its exterior a fiat face a,from which there is an opening 2) directly into the bore.

B is the valve-chest faced to fit the face a of the cylinder, but havinga projecting portion 0, which enters the opening 1). In the inner faceof this chest there is a cavity, the inner face of which is of arc form,as shown in Fig. 1, to constitute the seat for the valve 0, the face ofwhich is cylindric and has an arc of about and preferably somewhat morethan one hundred and eighty degrees, as shown in Fig. 1, the said arehaving its center approximately at the surface of the bore of thecylinder.

D is the piston, having the central portion of its length of so reduceda diameter that an annular space e is formed between it and the bore'ofthe cylinder to constitute a steamchest, and that inclined shoulders f fare formed to act upon the ends of the valve for producing andcontrolling its movement. The back of the valve,which is always incommunication with this space e, is hollowed out, as shown ate in Figs.1 and 2-, to give more steam-room.

The portion 0 of the valve-chest B which enters the openingh of thecylinder is made with checks d d, as shown in Figs. 2 and 3, toconstitute guides for the sides of the 'valve to guide the latter inplanes parallel with the length of the cylinder. In the valve-seat thereare ports 5 5*,communicating respectively with passages6 6*, leading toopposite en'dsof the cylinder, and there are also recesses g g* in theends communicating with the annular steam-space e. Between the ports 55* is arranged the exhaust-port h, from which a passage 2' runs throughthe chest and the wall of the cylinder, as shown in Fig. 2, to theexhaust-pipe connection j. In the back of the valve-chest there is asteam-space k, at either side of which there is a steam-pipe connectionl, and from which there is communication through a passage m in thechest and in the wall of the cylinder with the annular steam-space e inthe cylinder and'with the steam-space e in the back of the valve...

The valve has in it two coves nn*, arranged to bring either port 5 or 5*into communica tion. through the corresponding cavity g or g in the seatwith the steam-space, while the other port 5* or 5 is in communicationwith the exhaust-port h, 'andbetween these coves and its ends there areprovided through it two openings 0 to provide for a more direct and freesupply of steam from the spaces 6 and e to the ports 5 5*, the saidopenings never being closed. The exhaust-port h is made of such area inproportion to the ports 5 5* that the valve will be subject to asufficient excess of pressure from the steam under it to hold it to itsseat with sufficient pressure to prevent a reaction of the movement ofthe valve when its movement has been arrestedsuddenly by one endstriking the piston. By making the valve with a face havingan are ofabout or rather more than one hundred and eighty degrees, the center ofwhich is near the outside of the bore of the cylinder, those parts ofits face near the ends are substantially'or approximately normal or atright angles to the line of movement of the piston, and the consequenceis that when the inclines f f act upon the ends of the valve to move itthe direction of the pressure produced upon the valve is in thedirection of the line of the arc of its face and consequently in thedirection of least resistance, and the friction between the valve andseat resulting from such pressure and the wear of the valve, thevalve-seat, and the piston is reduced to a minimum, whereas when such avalve is, as has always heretofore been the case, constructed with anarc of chest fitted to said cylinder and comprising shorter radiusandlarger diameter, having its center near the center of the bore of thecylinder, the angle formed between the face of 1 the valve and the lineof movement of the piston is very acute, and the consequences are notonly that the pressure produced on the der and a piston in which is acavity forming valve by the piston for the purpose of movin g it tendsto press the valve forcibly against its. seat and produce great frictionbetween them, but that the valve is caused to act as a wedge between thevalve-seat and the straight portion of the piston which fits thecylinder, and thereby to grind and cut away the latter. The Valve whichis the subject of the present invention stops against the piston at aright angle thereto, and therefore cannot operate as a wedge in relationto it.

I have throughout this specification referred to steam as the motiveagent for an engine fitted with my improvement, but it is obvious thatthe improvement is just as applicable to an engine in which compressedair, gas, or other fluid under pressure is used for the motive power.

What I claim as my invention is- 1. In an engine, the combination with acylinder fitted with a piston having inclines for operating a valve, anda valve-seat of arc form on said cylinder, of a valve of correspondingform fitted to said seat and having the end portions of its face normalor approximately at right angles to the line of motion of the pistonwhereby it is caused to stop against the piston approximately at a rightangle thereto, substantially as and for the purpose herein set forth.

2. The combination with an engine cylinder having an opening in onesidethereof, a valvean are formed valve-seat and valve guiding cheeksprojecting'within said opening, and a valve fitted to said seat betweensaid guiding i cheeks, substantially as herein set forth.

3. The combination with the engine cylina steam space between thecylinder and piston, of a valve-chest upon said cylinder containing anarc-formed valve-seat, and a hollow arc-formed valve having a cavity inits back in communication with said steam space and having providedthrough it near its ends openings 0 0 forming free communication at alltimes between the aforesaid space and the valve-chest, substantially asherein set forth.

HENRY C. SERGEANF.

Witnesses: FREDK. HAYNES, LIDA M. Eonnn'r.

